The invention relates to an at least partially percussive electrical hand tool machine having a portable housing and a striking mechanism module vibrationally-damped thereto, in particular a chisel hammer.
The pneumatic striking mechanism, in percussive electrical hand tool machines, usually driven by an electric motor and the interaction of the work piece with the percussive tool cause inertia-related vibrations that are transmitted through the housing to the operator, in the frequency range of 1 Hz to 100 Hz, which should be suppressed as much as possible. These type of striking mechanism modules that are vibration-damped using a spring to the housing are limited displaceable, approximately 10 mm, for producing a different pre-stressing along the striking axis and vibrate about this central position with an amplitude of a few millimeters.
According to GB 215 4 497, an electrical hand tool machine has a striking mechanism module that is vibration damped by the housing, wherein the electrical motor that is solidly connected to the housing has a limited moveable engagement along the striking axis in the striking mechanism module.
According to DE 100 0 8671, the electrical motor, in an electrical hand tool machine, is connected to the housing via long, freely suspended lines. Such long, freely suspended lines have a very low resistance to bending because of their punctiform cross section and have a low intrinsic resonance relative to bending vibration modi, which can undergo a resonant excitation in the event of vibrations and which can result in failure due to material fatigue.
In addition, according to EP 0 276 313, a flat ribbon like cable harness between parts of a robot limited moveable relative to each other has a moveable flat rigid supporting structure, to which the cables are fastened. According to U.S. Pat. No. 5,054,944, a moveable printing head has a flat ribbon like cable harness that is flexible in one dimension and is a flexible circuit board made of plastic, which extends along the movement.